The present invention relates to a detecting method and an apparatus for detecting a condition of waves in permanent wave hairdressing.
Permanent wave hair is produced with hair curled on a number of rods using tools and chemical liquid for waving in a cold manner or otherwise in a hot manner. The condition of waves must be ensured by locally rewinding the curl after a constant lapse of time, by feeling with ones fingers, and by observation in either the cold or hot prior art manner. Thus such an experimental technique requires that a sixth sense be used. However, such conventional method are disadvantageous in that the hair is insufficiently permed or damaged due to errors in timing adjustment since the wave set requires a constant lapse of time. These methods are ineffective and it is troublesome to inspect the wave condition everytime, in particular, in a crowded beauty saloon.
More specifically, there are many differences of the conditions of the permanent waves due to individual differences of hair properties, and even in one person there are delicate differences in the time period required for suitable permanent waves due to factors such as hair temperature, hair condition and health, a temperature difference in seasons, a kind of chemical liquid for waves and the like.
For this reason, the beautician must hairdress always in the optimum condition preparing cards in which individual hair properties, a required time for the wave set, and the like are recorded.